1. Field
The present disclosure relates generally to microphones, and more particularly, to wireless microphones for automobiles.
2. Introduction
Communication devices, such as two-way radios, mobile telephones, and the like, are often used in automobiles to enable the driver to communicate with various people at stationary locations and in other vehicles. Although these devices are quite convenient, they have significant drawbacks. The driver is often required to steer the vehicle with one hand and operate the device with the other. This can be distracting and lead to inattentive driver behavior. Thus, it is preferable for these communication devices to operate hands-free, such that the driver does not need to hold the device while talking.
Various systems have been implemented or proposed in the literature to provide hands-free operation. These systems include a microphone and an audio speaker coupled to the communications device. The microphone is typically mounted in the vehicle somewhere in the vicinity of the driver and the audio speaker is generally positioned remote from the microphone to assist in minimizing feedback from the audio speaker to the microphone. By way of example, it is not uncommon to use
Bi-directional communication systems include an audio speaker and a microphone. In order to improve hands-free performance in a vehicle communication system, a microphone is typically mounted near the driver's head. For example, a microphone is commonly attached to the vehicle visor or headliner using a fastener such as a clip, adhesive, hook-and-loop fastening tape (such as VELCRO® brand fastener), or the like. The audio speaker associated with the communication system is preferably positioned remote from the microphone to assist in minimizing feedback from the audio speaker to the microphone. It is common, for example, for the audio speaker to be located in a vehicle adaptor, such as a hang-up cup or a cigarette lighter plug used to provide energizing power from the vehicle electrical system to the communication device. Thus, although the communication system designer knows the position of the audio speaker in advance, the position of the microphone is unknown as the user can position the microphone where they choose. The position of the microphone relative to the person speaking will determine the level of the speech signal output by the microphone and may affect the signal-to-noise ratio. The position of the microphone relative to the audio speaker will impact feedback between the speaker and microphone. Accordingly, the performance of the audio system is subject to the user's installation of the microphone. Additionally, the microphone will typically include a wire, which if it is mounted to the surface of the vehicle interior, will not be aesthetically pleasing. Alternatively, if the wire is to be mounted behind the interior lining, the vehicle interior must be disassembled and then reattached so that the wire can be hidden, which may result in parts that rattle loudly or hang loosely from the vehicle frame.